184 BYZANTINE CHURCHES CHAP. S. John the Baptist, stood near the church of the Holy-Apostles close to the western , end of the aqueduct of Valens. It might3 so far as the Indication cnear the aqueduct5 gives any clue3 be the sanctuary of the latter House.j in which case the church was dedicated to S, Anastasius.1 But the architectural features of Kalender Haneh Jamissi do not belong to the period before Justinian. Mordtmann2 identifies the building with the church of the Theotokos in the district of the Deaconess (j>ao9 rr}$ deoro/cov fa &taicovia'<r77<?), and ill favour of this view there is the fact that the site of the mosque corresponds5 speaking broadly, to the position which that church is known to have occupied somewhere between the forum of Taurus (now represented by the Turkish War Office) and the Philadelphium (the area about the mosque of Shahzad6)j and not far off the street leading to the Holy Apostles. Furthermore^ the rich and beautiful decoration of the church implies its importance^ so that it may very well be the church of the Theotokos Diaconissa, at which imperial processions from the Great Palace to the Holy Apostles stopped to allow the emperor to place a lighted taper upon the altar .of the shrine.8 Theophanes,4 the' earliest writer to mention the church of the Diaconissa5 ascribes its foundation to the Patriarch Kyriakos (593-605) in the fourth year of his patriarchate, during the reign of the Emperor Maurice. According to the historical evidence at our command, that church was therefore erected towards the close of the sixth century. Dr. Freshfidd,6 however, judging by the form of the church and the character of the dome, thinks that Kalender Haneh Jamissi is £ not earlier than the eighth century, and not later than the tenth.' Lethaby6 places it in the period between Justinian the Great and the eleventh century. *The 1 In the Epistle to Pope Agapetus the monastery *near the aqueduct* is described as * Anastasii prope Agogum,* Mansi, viii. p. 907. 2 Esquisses top. p. 70. 3 Const. Porphr, D£ cer. i. p. 75. 4 P. 428 ; Banduri, i, p. 18 ; viii. pp. 697-98. 6 Archaeologta, vol. lv. part 2, p. 438. 6 Mediaeval Art, p, 66.